<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=<device-width>, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <h1>hhh</h1>
</body>
<script src="./demo2.js"></script>
</html>


console.log("Hello World");
function sayHello(){
    alert('Hello JavaScript')
}
sayHello();